HP Pavilion 14-ce3511sa G7AL-2G DAG7ALMB8C0 REV: C

[tccyo22]

Hey there, I've got a HP laptop that is not powering on however the charger light is white and present however the 3v and 5v rails are not present as both IC's are missing their S5_ON enable signal. I was looking at a similar schematic and I see it comes from the IT5570E-128 chip (the one in the schematic is an IT8987 but I assume pin layout is similar enough?)

Some voltages I've measured as I'm not entirely sure what allows this chip to enable the S5_ON signal but VCC is at least missing.

VCC - 0v
3VPCU - 3.351v
V_ECACC - 3.351v
3V_VSTBY - 3.351v
ACIN - 2.533v

I'd like to get a better understanding how these ITE chips function, especially when it comes to producing the S5_ON for the 5v and 3v rails.

The main concern for me right now is the lack of the VCC voltage. I assume this is one of the required power rails for the chip?

[mon2]

Review the VCC pin region and often there will be a SOT23 (3 legged; dual diode with common cathode variation) nearby. This dual diode will have a voltage feed from a local RTC clock battery (CR2032?) or from an always on power rail regulator. The always on power regulators are usually after the DCin mosfets are enabled. So if the alw rails are OFF, then the DCin mosfets are not on or defective. Confirm the power path from the DC connector for the power adapter and then the usual DCin mosfets that should follow. Which exact mosfets do you have onboard? Which part # ?

If N-channel type (common) then the gate pin voltage should be higher than the source / drain voltages to enable. This boosted voltage should be ~25 volts to enable and often from the ACDRV pin of the BQ series charger IC by Texas Instruments. Yours may be the same or from Intersil (ISL). Share all of the details or post pics for the review.

The ITE chip is usually a 8051 based GPIO controller that handles tasks like RTC, keyboard, etc. The firmware may be onboard or via external flash local rom or spoon fed from another more powerful local host nearby over SPI interconnect.

[mcplslg123]

On many newer boards,3V/5V wont be available on coil in standby due to deep sleep well technology.S5_ON is released by SIO after pressing power button on many motherboards. So check whether its expected in standby or not.

[tccyo22]

Thanks for the information you guys. This actually helped me alot. Especially the fact when it comes to the 5v and 3v rails on newer boards not being present on standby.

I had a full post ready about how my charging IC was an ISL88379B and couldn't find the datasheet for pins but had a diagram and I had my 19v present and the main DCin with 19v and 25v boosted gate etc.

However in the end it all came back to my visual inspection being bad. The RAM slot on this model we've had loose pins that weren't soldered properly before but this was not the case this time. Upon getting the voltages near the IT chip I saw one pin was not reflecting like the others off the edge of my scope so I tapped it with my tweezer and it fell in. Seems a single pin had snapped on the SO-DIMM slot...

Anyway 1 borrowed pin from a donor board later and the laptop is up and running just fine, how a pin can snap is baffling to me but I appreciate the guidance on helping me understand the standby and power rails on this model better.

Included a pic of the broken pin in attachments.

[mcplslg123]

Newer HP boards Ram slots are pathetic in terms of quality.Every other HP mb comes with ram slot issue.